High-quality uniform monoatomic layer of graphene deposited on copper foil by Chemical Vapor Deposition (CVD).
Graphene on the top has been coated using thin layer of PMMA. Graphene has been removed from the bottom side from easier electrochemical delamination or etching.

Uniform monolayer of graphene protects copper against oxidation. Graphene has been partially removed from the top side, which will allow oxide from the air to reach the copper underneath the graphene. This process can be speeded up by dipping the sample in hydrogen peroxide.